The invention relates to meteoroid capturing devices and is directed more particularly to one employing a cavity (or cell) covered by a thin membrane.
There are three ways in which meteoroids have been studied and analyzed in the past. One way has been to analyze meteorites, i.e., the remnants that one finds on the ground, of meteoroids which have passed through the atmosphere. There are reasons to believe, however, that only a special class of meteoroids do not burn completely upon their entry into the atmosphere, thereby leaving a remnant (meteorite) which can be analyzed. Hence, the analysis of meteorites may give a distorted view of the general composition of meteoroids. Another technique is to analyze the spectra of meteor trails, the fiery trail made by an incoming meteoroid. However, this technique is presently beset with considerable difficulty and uncertainty.
A third technique, developed relatively recently, works as follows: A set of meteoroid interaction surfaces, shaped somewhat like a semi-open venetian blind, is launched into space. Behind the interaction surfaces, a strong electric field is applied to accelerate positive ions toward a current measuring device. When a meteoroid strikes one of the interaction surfaces, part of it is spewed off as an ionized vapor. The positive ions in this ionized vapor are then accelerated toward the charge collector. The ratio of electric charge to mass of the various species of positive ions determines their respective times of arrival relative to the detection of electrons near the interaction surfaces. This technique suffers from problems similar to those encountered in analyzing meteor trails. Namely, the probability of ionization of the various species of elements under hypervelocity impact conditions is not well known and therefore the original meteoroid composition cannot be accurately determined.